Artificial leather product



Patented Mar. 18, 1947 UNITED STATES PATENT OFFICE ARTIFICIAL LEATHER PRODUCT Felix J. Bellac, New York, N. Y.

No Drawing. Application April 6, 1944, Serial No. 529,835

3 Claims. 1.

This invention relates to artificial leather prodnets and more particularly to artificial leather products comprising as a base a rubber coated fabric provided with nitrocellulose containing coatings.

It has been known in the art to manufacture artificial leather products by applying to a fabric base, for example a cotton fabric, suitable provide an artificial leather product or patent leather of the above mentionedtype, in which the fabric base consists of a rubber coated fabric, and the plastic surface layers consist of nitrocellulose containing coatings which are in durable, uniform and homogeneous connection with said rubber coated fabric base.

Another object of my present invention .is to provide an intermediate nitrocellulose coat which firmly and uniformly adheres to a rubberized fab ric base and forms a uniform and homogeneous connection with nitrocellulose containing top coats or finishing coats applied to said intermediate coat.

It is also an object of this invention to provide a nitrocellulose lacquer composition, which can be applied as a coat to textile fabrics and forms a firm, durable and homogeneous connection with said fabrics.

Other objects and the advantages of my invention will be apparent to those skilled in the art from the appended claims and the following specification which describes, by way of example, some preferred embodiments of the invention.

I have found that cellulose nitrate containing coatings forming a firm, durable and homogeneous: coat or finish on rubberized fabric may be obtained by first applying to the rubber coated fabric an intermediate nitrocellulose coating ot the type described hereinafter, and then applying to said intermediate coating one or more coats. of customary nitrocellulose lacquers. According to my invention'said intermediary nitrocellulose coating is obtained by using a solution containing cellulose nitrate, 'a synthetic resinous substance compatible with cellulose nitrate, pigment and plasticizers for cellulose nitrate and said synthetic resinous substance, in the presence of a relatively small amount of butyl stearate, and suitable diluents. In these solutions, as solvents,

The main object of the present invention is tofor example, esters, ethers and ketones, such as amyl acetate, ethyl acetate, butyl acetate and acetone may be used. The synthetic resinous substances added to the cellulose nitrate solution are alkyd resins obtained from one or more polyvalent alcohols, such as glycerine, one or more polybasic acids, such as phthalic acid, phthalic anhydride, adipic acid, succinic acid, and one or more drying oils and/or drying oil acids with or without the addition of one or more further modifying agents, such as natural or synthetic resinous materials. It is to be understood that in the present specification and the appended claims the term alkyd resin is used to denote and inelude resins resulting from the interaction of the above mentioned ingredients and compatible with nitrocellulose. As examples of the plasticizers, dibutylphthalate, dibutylsebacate, tributylphosphate, tricresylphosphate, blown castor oil, and raw or blown rapeseed oil, may be mentioned. I have found, however, that the use of certai resinous substances, which are capable of acting as plasticizers, give particularly good results. Such resinous substances are the materials sold under the trade-name paraplex. These materials may be used in mixture with the alkyd resin or resins or instead of the alkyd resins. Mixtures of several plasticizers may also be used. In order to obtain a satisfactory intermediate coating, i. e., a coating which forms a permanent, homogeneous and uniform connection with the rubberized fabric, and in which the nitrocellulose and other film-forming ingredients form a durable, homo-' geneous blend, I add a relatively small amount,

', i. e., 2-5%, preferably about 3% by weight of,

butylstearate to the nitrocellulose-resin solution. As examples of the diluting agents used in pre-, paring this solution, alcohols and hydrocarbons,

such as denatured ethyl-alcohol and solvent naphtha may be mentioned. Instead of the butyl stearate a mixture of butylstearate with Venetian turpentine resin may also be used.

I have further found that the addition of certain organic compounds acting as interfacial tension reducing agents facilitates the formation of a strongly and uniformly adhering coating on the rubberized fabric base, and results in particularly homogeneous, durable products. The use of di-octyl sodium sulfosuccinate in an amount of (Ll-0.5% (based upon the total weight of the nitrocellulose solution) has been found very useful.

After the application of the above described first or intermediate coat to the rubberized fabric base, the coat is dried, the dried material is cured, and may then be provided with one or more nitrocellulose coatings or finishes as known in the manufacture of artificial leather or patent leather products. For example, the compositions described in..my. prior Patent No. 2,326,-

992, patented August 1'7, 1943, may be used with advantage. These coating compositions consist of nitrocellulose and plasticizers dissolved in a mixture of. solvents and .diluents; with or with-.- out the addition of pigments.

Example I.A solution to be app to a rubberized fabric as an intermediate coat consists of the following ingredients:

' Per cent Cellulose nitrate (a mixture of equal parts i of wet nitrocellulose of 5-6 seconds vis cosity and wet nitrocellulose of 30 seconds viscosity 15-30 A solvent consisting'of 20-80% of ethyl acetate and 80-20% of acetone 15-30 Dibutylphthalate 3- 8 Alkyd-resin A r 12-22 Black past ,5-10

Denatured alcohol 410-30 Butylstearate (based on thetotabweig-ht of the. above ingredients) .3

The alkyd resin .Aused in the above composition was the reaction product of "12 parts by weight of glycerol, 14-parts by weight-of phtha'lic anhydride, 55 parts by weight of linseed oil acids and 18 parts by weight of rosin.

After applying a coating of the above-composition to said rubberized base, and drying the coated base, a top coat is provided by applying a lacquer of the composition described in one 7 of the examples of myabove mentioned prior Patent No. 2,326,992. r

Example II.A composition consisting of Parts by weight The nitrocellulose as used in theintermediate coat of Example L .50 Acetone .50 Ethylacetate 2.5 Dibutylphthalate .10 fParaplexRegn2 The alkyd resin known under the :tradename Aroplaz .930. 20 Black past .25 Denatured alcohol Butylstearate 5 is "applied as the intermediate coat to a rubberized fabric. 'The top coat applied to the intermediate coat mayhave the same composition as in Example I.

Example lII.--The intermediate coat to be applied to a rubberized fabric base is produced from a composition consisting .of the following ingredients:

' Parts by weight The nitrocellulose .as used in the intermediate coat of Example I 50 Acetone 50 Ethylacetate 25 Dibutylphthalate 10 Paraplex Reg. 2 35. Black past 25 Denatured alco 25 Butyl steara ...5 Di-'-octyl sodium :sulfosuccinate 1.0

The top coat on this intermediate coat isl roduced from a composition consisting .ofthe' following-ingredients:

' g V Parts. :by weight Nitrocellulose ctps' .50 Nitrocellulose second viscosity .50 Dibuty lphthalate 25 Butanol 30 Blown rapeseed 11.... .15 Solvent n p Example I V.-A composition consisting of Nitrocellulose. as used in Example I 15-30 A solvent .consisting of v10% ethyl acetate, 35% of butyl acetate, 5% of amyl acetate, and 50% of acetone 15-30 Dibutyl phthalate ,3- 8 Alkyd resin 12-22 Black p s 5-10 Denatured alcohol 10-30 Butyl rstear t 3 is used for producin an intermediate coat ,on a rubberized fabric base. The alkyd resin B used in this composition was produced from 17 parts by weight of =g-lycemh 2'7. parts by weight of phthalic :anhydride. andr55 parts. byweight-of linseed oil acids. The top .coat on this interme-. diate .coat. maybe produced .from the. .top coat lacquer described in Example I.

Insteadof .the above described alkyd resin B, a resin formed-1mm 11 par'tsfby weight of ycol,

1.5 parts .by weight of phthalic anhydride, '65

parts by weight of linseed .oil acids and 15 parts by weight. of rosin may also be used. I

Example I .A composition consisting of Parts by weight The nitrocellulose as used inthe intermediate coat of Example I 50 Acetone '50 Ethylacetat'e 251 Dibutylphthalate' ,1 0 Paraplex Reg. 2 1'5. Alkyd resin C- 20 Pigment paste 2 5 Denatured 'alcohol r25 Butyll'stearat i5 is applied as. the intermediate coat ?to :a rubberized fabric. The coated fabricis dried and cured and-a topcoat of theiollowing compositionisthen applied to'the intermediate X0031?! Parts by weight Nitrocellulose'30-35 ctps =60 Nitrocellulose A sec. viscosity 40 Dibutylphthalate 25 Butanol 20 Solvent naphtha 40 Blown castor oil '15 line-alkyd resin C used .in the above composition was obtained from 10 partsby weight of glycerol, 3.5 parts by weight of vphthalic anhydride; parts by weight of linseed oil .acids and isapplied as an intermediate coat to a rubber.- ized fabric. The top coat applied to the intermediate coat may have the. same composition as in Example. V. a

I'have vfound that by using the above described compositions containing nitrocellulose anda synthetic resin of the .above'described typeltogether.

with butylstearate, very satisfactory products are obtained, in which the coatings applied to the rubberized fabric strongly and uniformly adhere thereto, and which represent flexible, durable artificial leather or patent leather products of excellent properties and appearance.

It is to be understood that in the present specification and the appended claims the terms intermediate coat and "top coat denote coatings which are obtained in a manner Well known per se to those skilled in the art by the subsequent application of several layers-for example 2-5 layers-to the base to be coated. Thus, my "intermediate coat may be obtained by applying a, first layer of the compositions described above, and then applying several further layers to the first layer. Similarly, the top coat described in my examples is also obtained by the subsequent application of several layers.

I have found it advantageous to add to the composition used in th first layer of the top coat, 1. e., in the layer contacting the intermediate coat, a certain amount of aroplaz or paraplex. Aroplaz 930 or paraplex reg. 2 may be added to said composition in an amount of 5-15%.

It is to be understood that in the present specification and the appended claims by the term rubberized fabric I mean a fabric base material of any desired type, th fibers of which are coated or impregnated with natural, synthetic or reclaimed rubber. By the term nitrocellulose coat I mean a nitrocellulose coating composition as described in my above mentioned prior Patent No. 2,326,992 or an'equivalent nitrocellulose-containing composition. These compositions may also contain pigments, if desired.

In carrying out my present invention, the above described intermediate coat may be applied to a vulcanized rubberized fabric, and the fabric provided with the intermediate coat is then subjected to dryin for example at 140-160 F. before the application of the top coat layers. However, rubberized unvulcanized fabrics may also be treated according to my invention by applying intermediate base coat layers to the unvulcanized, rubberized fabric, and subjecting the coated material to heating at temperatures, at which curing of the rubber and drying of the intermediate coat takes place. In general, gradual heating of the coated material to 260 F. and then heating of the same at this temperature for one or several hours i suificient to effect drying of the varnish and vulcanizing of the rubber.

It will be understood from the above description that my invention is susceptible of numerous modifications, and it is to be understood that I do not limit myself to the above specific examples and details described except as defined in the appended claims.

I claim:

1. As an article of manufacture, a coated flexible fabric sheeting comprising a rubberized fabric base provided with an intermediate coating containing about 15-30% of cellulose nitrate, about 15-30% of a solvent, about 3-8% of dibutylphthalate, about 12-22% of alkyd resins having plasticizing properties, about 25% butylstearate, about 10-30% of diluents, about 5-10% of pigments, and about 01-05% of dioctyl sodium sulfosuccinate, and a final nitrocellulose coating applied to said intermediate coating,

2. As an article of manufacture, a coated flexible fabric sheeting comprising a rubberized fabric base provided with an intermediate coating containing about 15-30% of cellulose nitrate, about 15-30%. of a solvent, about 3-8% of dibutylphthalate, about 12-22% of alkyd resins having plasticizing properties, about 2-5% butylstearate, about 10-30% of diluents, about 5-10% of pigments, and about 0.1-0.5% of dioctyl sodium sulfosuccinate, and a final nitrocellulose coating, said final nitrocellulose coating consisting of a, cellulose nitrate which is soluble in ethyl alcohol, is dissolved in a mixture of ethyl alcohol with toluene, xylene and butyl alcohol, and a plasticizer selected from the group consisting of blown rape seed oil and blown castor oil, applied to said intermediate coating.

3. As an article of manufacture, a coated flexible fabric sheeting comprising a rubberized fabric.

base provided with layers of an intermediate coating containing about 15-30% of cellulose nitrate with about 12-22% of alkyd resins having plasticizing properties, the amount of cellulose nitrate in said intermediate coating being greater than that of the alkyd resin, said intermediate coating further containing about 15-30% of a solvent, about 3-8% of dibutylphthalate, about 2-5% butyl stearate, about 10-30% of diluents, and about 5-10% of pigments, said fabric sheeting also comprising layers of a final nitrocellulose coating applied to said intermediate coating.

FELIX J. BELLAC.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,324,154 Howlett Dec. 9, 1919 2,061,528 Trolander et al Nov. 17, 1936 2,190,705 Dreyling et al Feb. 20, 1940 2,223,575 Pitman Dec. 3, 1940 2,275,716 Bachman May 10, 1942 1,818,575 Parrett Aug. 11, 1931 2,171,389 Cate Aug. 29, 1939 

